The Biomarkers Core contributes to the overall program project in the; a) collection of large numbers of biologic samples in support of Projects 1, 2, and 3, b) storage and archiving of all biologic samples, c) histologic services for the sectioning of tissue blocks in support of Projects 1, 2, and 3, d) pathology review of ail tissue samples (Projects 1, 2, and 3), d) standardization of sample acquisition, fixation and/or time to freezing, and sample storage, e) distribution of samples from Projects 1, 2, and 3 to co-Investigators/collaborators, in the case of assays done off-site, f) measurement of biomarker expression in skin biopsies (Projects 1, 2, and 3), and g) measurement of agent levels in blood and periodic quality control of agents developed for clinical application in support of Core D (Project 3). We have evaluated, analyzed, and optimized assays used in the Biomarker Core and have an extensive history of measurement of analytes in both plasma and serum. In collaboration with Biometry and Data Management (Core B), the Biomarker Core has carried out the sample analyses and interacted with each Project on the transfer and/or analysis of samples, as well as on the management and interpretation of the results. Assays provided by the Core will include immunohistochemical method development and analysis, karyometric sample preparation, as well as the measurement of agent levels in skin and blood. The Core has added a proteomic methodology, Reverse Phase Protein Microarray (RPMA), a novel application for multiplexed quantitative measurement of multiple signaling proteins, many of which are phosphoproteins, from biological specimens. RPMA represents a novel means of measurement of hundreds of proteins from a single specimen. A second novel methodology in this Program Project is quantitative Nuclease Protection Assay (qNPA), a method for mRNA analysis from small tissue sections of formalin fixed paraffin embedded (FFPE) samples of selected genes arrayed onto a platform. qNPA will be a developmental aim in the Program Project and each project selected specific genes to be arrayed onto this platform including genes associated with skin cells and their transition into cancer and metastasis. This highly interactive and clinically translational research program project focuses on the successful preclinical testing of targeted chemoprevention agents in innovative mouse models (Projects 1 and 2) followed by the design and implementation of clinical trials in at risk human populations (Project 3). Detailed descriptions of the decision-tree selection process as well as the interactions between Projects and Cores are found on the Resources Format Page.